[Federal Register Volume 91, Number 45 (Monday, March 9, 2026)]
[Proposed Rules]
[Pages 11191-11194]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 2026-04526]


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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. FAA-2026-2292; Project Identifier MCAI-2024-00043-R]
RIN 2120-AA64


Airworthiness Directives; Airbus Helicopters

AGENCY: Federal Aviation Administration (FAA), DOT.

ACTION: Notice of proposed rulemaking (NPRM).

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SUMMARY: The FAA proposes to adopt a new airworthiness directive (AD) 
for all Airbus Helicopters Model AS 350B2, AS 350B3, EC120B, and EC 130 
B4 helicopters. This proposed AD was prompted by a short-circuit due to 
foreign object debris (FOD) or dust inside the lighting and ancillaries 
control unit (LACU). This proposed AD would require repetitively 
cleaning and inspecting the affected LACU for FOD. Depending on the 
configuration of your helicopter, this proposed AD would also require 
modifying the emergency floatation system (EFS) activation switches and 
revising the existing rotorcraft flight manual (RFM) for your 
helicopter, which would constitute terminating action for the proposed 
repetitive cleaning and inspection requirements. Additionally, this 
proposed AD would prohibit installing an affected LACU on any 
helicopter unless certain requirements are met. The FAA is proposing 
this AD to address the unsafe condition on these products.

DATES: The FAA must receive comments on this NPRM by April 23, 2026.

ADDRESSES: You may send comments, using the procedures found in 14 CFR 
11.43 and 11.45, by any of the following methods:
     Federal eRulemaking Portal: Go to regulations.gov. Follow 
the instructions for submitting comments.
     Fax: (202) 493-2251.
     Mail: U.S. Department of Transportation, Docket 
Operations, M-30, West Building Ground Floor, Room W12-140, 1200 New 
Jersey Avenue SE, Washington, DC 20590.
     Hand Delivery: Deliver to Mail address above between 9 
a.m. and 5 p.m., Monday through Friday, except Federal holidays.
    AD Docket: You may examine the AD docket at regulations.gov under 
Docket No. FAA-2026-2292; or in person at Docket Operations between 9 
a.m. and 5 p.m., Monday through Friday, except Federal holidays. The AD 
docket contains this NPRM, the mandatory continuing airworthiness 
information (MCAI), any comments received, and other information. The 
street address for Docket Operations is listed above.
    Material Incorporated by Reference:
     For European Union Aviation Safety Agency (EASA) material 
identified in this proposed AD, contact EASA, Konrad-Adenauer-Ufer 3, 
50668 Cologne, Germany; phone: +49 221 8999 000; email: 
[email protected]; website: easa.europa.eu. You may find the EASA 
material on the EASA website at ad.easa.europa.eu.
     You may view this material at the FAA, Office of the 
Regional Counsel, Southwest Region, 10101 Hillwood Parkway, Room 6N-
321, Fort Worth, TX 76177. For information on the availability of this 
material at the FAA, call (817) 222-5110. It is also available at 
regulations.gov under Docket No. FAA-2026-2292.

FOR FURTHER INFORMATION CONTACT: Deep Gaurav, Aviation Safety Engineer, 
FAA, 1600 Stewart Avenue, Suite 410, Westbury, NY 11590; phone: (817) 
228-3731; email: [email protected].

SUPPLEMENTARY INFORMATION:

Comments Invited

    The FAA invites you to send any written relevant data, views, or 
arguments about this proposal. Send your comments to an address listed 
under ADDRESSES. Include ``Docket No. FAA-2026-2292; Project Identifier 
MCAI-2024-00043-R'' at the beginning of your comments. The most helpful 
comments reference a specific portion of the proposal, explain the 
reason for any recommended change, and include supporting data. The FAA 
will consider all comments received by the closing date and may amend 
this proposal because of those comments.
    Except for Confidential Business Information (CBI) as described in 
the following paragraph, and other information as described in 14 CFR 
11.35, the FAA will post all comments received, without change, to 
regulations.gov, including any personal information you provide. The 
agency will also post a report summarizing each substantive verbal 
contact received about this NPRM.

Confidential Business Information

    CBI is commercial or financial information that is both customarily 
and actually treated as private by its owner. Under the Freedom of 
Information Act (FOIA) (5 U.S.C. 552), CBI is exempt from public 
disclosure. If your comments responsive to this NPRM

[[Page 11192]]

contain commercial or financial information that is customarily treated 
as private, that you actually treat as private, and that is relevant or 
responsive to this NPRM, it is important that you clearly designate the 
submitted comments as CBI. Please mark each page of your submission 
containing CBI as ``PROPIN.'' The FAA will treat such marked 
submissions as confidential under the FOIA, and they will not be placed 
in the public docket of this NPRM. Submissions containing CBI should be 
sent to Deep Gaurav, Aviation Safety Engineer, FAA, 1600 Stewart 
Avenue, Suite 410, Westbury, NY 11590. Any commentary that the FAA 
receives which is not specifically designated as CBI will be placed in 
the public docket for this rulemaking.

Background

    EASA, which is the Technical Agent for the Member States of the 
European Union, issued EASA AD 2021-0168, dated July 16, 2021 (EASA AD 
2021-0168), to correct an unsafe condition on all Airbus Helicopters 
Model EC120B helicopters and on Model EC 130 B4, AS 350B2, and AS 350B3 
helicopters with certain modifications installed. EASA AD 2021-0168 
stated that during a flight on a Model EC 130 B4 helicopter, a ``strong 
burnt smell'' and smoke appeared in the cockpit, which activated visual 
and aural alarms. An investigation revealed that the root cause of this 
occurrence was a short circuit inside the LACU, which was probably 
caused by the presence of FOD or dust. EASA AD 2021-0168 further stated 
that failure of the LACU, if not detected and corrected, could lead to 
the loss of the EFS, resulting in failure of the EFS to activate during 
an emergency water landing. Due to the design similarities, EASA AD 
2021-0168 stated the unsafe condition can also exist or develop on 
Model EC120B helicopters and on certain Model AS 350-series 
helicopters. Depending on the configuration of the helicopter, EASA AD 
2021-0168 required either a one-time inspection and cleaning of the 
affected parts or repetitive inspections and cleaning of the affected 
parts and, depending on findings, accomplishment of applicable 
corrective actions. EASA AD 2021-0168 also included requirements for 
the installation of affected parts.
    EASA superseded EASA AD 2021-0168 with EASA AD 2024-0018, dated 
January 11, 2024 (EASA AD 2024-0018) (also referred to as ``the 
MCAI''), after determining that the unsafe condition can only develop 
if the helicopter is equipped with an EFS. Consequently, Airbus 
Helicopters developed a modification of the EFS activation buttons to 
allow the use of the EFS function even in the event of an LACU failure. 
The MCAI partially retains the repetitive cleaning and inspection 
requirements in EASA AD 2021-0168 and requires modifying certain 
helicopters as terminating action for the cleaning and inspections. 
Concurrently with the modification, the MCAI requires revising the 
existing RFMS (Rotorcraft Flight Manual Supplement) for the helicopter 
to include information and updated procedures that reflect the 
modification to the EFS activation buttons.
    For further information, you may examine the MCAI in the AD docket 
at regulations.gov under Docket No. FAA-2026-2292.

Material Incorporated by Reference Under 1 CFR Part 51

    The FAA reviewed EASA AD 2024-0018, which specifies procedures for 
cleaning and repetitively inspecting the LACU for FOD. EASA AD 2024-
0018 also specifies procedures for amending the RFMs and modifying the 
location of EFS activation switches on certain helicopters, which 
constitutes terminating action for the repetitive inspection 
requirements. Lastly, EASA AD 2024-0018 prohibits installing certain 
EFS and LACUs on any helicopter, unless certain requirements are met.
    This material is reasonably available because the interested 
parties have access to it through their normal course of business or by 
the means identified in the ADDRESSES section.

FAA's Determination

    These products have been approved by the civil aviation authority 
(CAA) of another country and are approved for operation in the United 
States. Pursuant to the FAA's bilateral agreement with this State of 
Design Authority, it has notified the FAA of the unsafe condition 
described in the MCAI referenced above. The FAA is issuing this NPRM 
after determining that the unsafe condition described previously is 
likely to exist or develop on other products of the same type design.

Proposed AD Requirements in This NPRM

    This proposed AD would require accomplishing the actions specified 
in EASA AD 2024-0018, described previously, as incorporated by 
reference, except for any differences identified as exceptions in the 
regulatory text of this proposed AD. See ``Differences Between this 
Proposed AD and the MCAI'' for a general discussion of these 
differences.

Differences Between This Proposed AD and the MCAI

    EASA AD 2024-0018 requires informing all flight crews of the 
revisions to the RFMS and thereafter operating the helicopter 
accordingly. However, this AD does not require those actions as those 
actions are already required by FAA regulations. FAA regulations 
require operators furnish to pilots any changes to the flight manual 
(for example, 14 CFR 135.21) and to ensure the pilots are familiar with 
the flight manual (for example, 14 CFR 91.505). FAA regulations also 
require pilots to follow the procedures in the existing flight manual 
including all updates. Therefore, including a requirement in this AD to 
inform the flight crew and operate the helicopter according to the 
revised RFMS would be redundant and unnecessary.

Explanation of Required Compliance Information

    In the FAA's ongoing efforts to improve the efficiency of the AD 
process, the FAA developed a process to use some CAA ADs as the primary 
source of information for compliance with requirements for 
corresponding FAA ADs. The FAA has been coordinating this process with 
manufacturers and CAAs. As a result, the FAA proposes to incorporate 
EASA AD 2024-0018 by reference in the FAA final rule. This proposed AD 
would, therefore, require compliance with EASA 2024-0018 in its 
entirety through that incorporation, except for any differences 
identified as exceptions in the regulatory text of this proposed AD. 
Using common terms that are the same as the heading of a particular 
section in EASA AD 2024-0018 does not mean that operators need comply 
only with that section. For example, where the AD requirement refers to 
``all required actions and compliance times,'' compliance with this AD 
requirement is not limited to the section titled ``Required Action(s) 
and Compliance Time(s)'' in EASA AD 2024-0018. Material required in 
EASA AD 2024-0018 for compliance will be available at 
www.regulations.gov by searching for and locating Docket No. FAA-2026-
2292 after the FAA final rule is published.

Costs of Compliance

    The FAA estimates that this AD, if adopted as proposed, would 
affect 576 helicopters of U.S. registry.
    The FAA estimates the following costs to comply with this proposed 
AD:

[[Page 11193]]



                                                 Estimated Costs
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                                                                              Cost per
               Action                        Labor cost         Parts cost    product     Cost on U.S. operators
----------------------------------------------------------------------------------------------------------------
Clean and inspect the LACU..........  2 work-hours x $85 per            $0         $170  $97,920 per inspection
                                       hour = $170 per                                    cycle.
                                       helicopter.
Modification of EFS.................  16 work-hours x $85 per            0        1,360  $783,360.
                                       hour = 1,360.
Revise RFM..........................  1 work-hour x $85 per              0           85  $48,960.
                                       hour = $85.
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Authority for This Rulemaking

    Title 49 of the United States Code specifies the FAA's authority to 
issue rules on aviation safety. Subtitle I, section 106, describes the 
authority of the FAA Administrator. Subtitle VII: Aviation Programs, 
describes in more detail the scope of the Agency's authority.
    The FAA is issuing this rulemaking under the authority described in 
Subtitle VII, Part A, Subpart III, Section 44701: General requirements. 
Under that section, Congress charges the FAA with promoting safe flight 
of civil aircraft in air commerce by prescribing regulations for 
practices, methods, and procedures the Administrator finds necessary 
for safety in air commerce. This regulation is within the scope of that 
authority because it addresses an unsafe condition that is likely to 
exist or develop on products identified in this rulemaking action.

Regulatory Findings

    The FAA determined that this proposed AD would not have federalism 
implications under Executive Order 13132. This proposed AD would not 
have a substantial direct effect on the States, on the relationship 
between the national government and the States, or on the distribution 
of power and responsibilities among the various levels of government.
    For the reasons discussed above, I certify this proposed 
regulation:
    (1) Is not a ``significant regulatory action'' under Executive 
Order 12866,
    (2) Would not affect intrastate aviation in Alaska, and
    (3) Would not have a significant economic impact, positive or 
negative, on a substantial number of small entities under the criteria 
of the Regulatory Flexibility Act.

List of Subjects in 14 CFR Part 39

    Air transportation, Aircraft, Aviation safety, Incorporation by 
reference, Safety.

The Proposed Amendment

    Accordingly, under the authority delegated to me by the 
Administrator, the FAA proposes to amend 14 CFR part 39 as follows:

PART 39--AIRWORTHINESS DIRECTIVES

0
1. The authority citation for part 39 continues to read as follows:

    Authority: 49 U.S.C. 106(g), 40113, 44701.


Sec.  39.13  [Amended]

0
2. The FAA amends Sec.  39.13 by adding the following new airworthiness 
directive:

Airbus Helicopters: Docket No. FAA-2026-2292; Project Identifier 
MCAI-2024-00043-R.

(a) Comments Due Date

    The FAA must receive comments on this airworthiness directive 
(AD) by April 23, 2026.

(b) Affected ADs

    None.

(c) Applicability

    This AD applies to all Airbus Helicopters Model AS 350B2, AS 
350B3, EC120B, and EC 130 B4 helicopters, certificated in any 
category.

(d) Subject

    Joint Aircraft System Component (JASC) Code 3100, Indication/
Recording System.

(e) Unsafe Condition

    This AD was prompted by a short-circuit due to foreign object 
debris or dust inside the lighting and ancillaries control unit 
(LACU) in a Model EC 130 B4 helicopter. The FAA is issuing this AD 
to prevent this malfunction. This unsafe condition, if not detected 
and addressed, could lead to loss of the emergency floatation system 
(EFS) and result in failure of the EFS to activate during an 
emergency water landing.

(f) Compliance

    Comply with this AD within the compliance times specified, 
unless already done.

(g) Requirements

    Except as specified in paragraphs (h) and (i) of this AD: Comply 
with all required actions and compliance times specified in, and in 
accordance with, European Union Aviation Safety Agency AD 2024-0018, 
dated January 11, 2024 (EASA AD 2024-0018).

(h) Exceptions to EASA AD 2024-0018

    (1) Where EASA AD 2024-0018 requires compliance in terms of 
flight hours, this AD requires using hours time-in-service.
    (2) Where EASA AD 2024-0018 refers to its effective date and to 
July 30, 2021 (the effective date of EASA AD 2021-0168, dated June 
16, 2021), this AD requires using the effective date of this AD.
    (3) This AD requires that paragraph (2) of EASA AD 2024-0018 
apply only to Group 1 helicopters as defined in EASA AD 2024-0018.
    (4) This AD does not adopt paragraph (3) of EASA AD 2024-0018. 
Instead, this AD requires that, during any inspection required by 
paragraph (1) or (2) of EASA AD 2024-0018, if foreign object debris 
or dust is found, you must clean the printed circuit board of the 
control panel. After the modification required by paragraph (4) of 
EASA AD 2024-0018, the helicopter is a Group 2 helicopter.
    (5) Where paragraph (5) of EASA AD 2024-0018 specifies to inform 
all flight crews and thereafter operate the helicopter accordingly, 
this AD does not require those actions as those actions are already 
required by existing FAA operating regulations (see 14 CFR 91.505 
and 14 CFR 135.21).
    (6) Where the material referenced in EASA AD 2024-0018 specifies 
to discard parts, this AD requires removing these parts from 
service.
    (7) Where the material referenced in EASA AD 2024-0018 specifies 
ensuring the applicable rotorcraft flight manual (RFM) is at the 
latest update, this AD only requires revising your RFM to the 
revision specified in the material and not to later revisions 
(updates).
    (8) This AD does not adopt paragraph (7.2) of EASA AD 2024-0018.
    (9) This AD does not adopt the ``Remarks'' section of EASA AD 
2024-0018.

(i) No Reporting Requirement

    Although the material referenced in EASA AD 2024-0018 specifies 
to submit information to the manufacturer, this AD does not require 
that action.

(j) Alternative Methods of Compliance (AMOCs)

    (1) The Manager, International Validation Branch, FAA, has the 
authority to approve AMOCs for this AD, if requested using the 
procedures found in 14 CFR 39.19. In accordance with 14 CFR 39.19, 
send your request to your principal inspector or local Flight 
Standards District Office, as appropriate. If sending information 
directly to the manager of the International Validation Branch, send 
it to the attention of the person identified in paragraph (k) of 
this AD and email to: [email protected].
    (2) Before using any approved AMOC, notify your appropriate 
principal inspector, or lacking a principal inspector, the manager 
of the local flight standards district office/certificate holding 
district office.

[[Page 11194]]

(k) Additional Information

    For more information about this AD, contact Deep Gaurav, 
Aviation Safety Engineer, FAA, 1600 Stewart Avenue, Suite 410, 
Westbury, NY 11590; phone: (817) 228-3731; email: 
[email protected].

(l) Material Incorporated by Reference

    (1) The Director of the Federal Register approved the 
incorporation by reference of the material listed in this paragraph 
under 5 U.S.C. 552(a) and 1 CFR part 51.
    (2) You must use this material as applicable to do the actions 
required by this AD, unless the AD specifies otherwise.
    (i) European Union Aviation Safety Agency (EASA) AD 2024-0018, 
dated January 11, 2024.
    (ii) [Reserved]
    (3) For EASA material identified in this AD, contact EASA, 
Konrad-Adenauer-Ufer 3, 50668 Cologne, Germany; phone: +49 221 8999 
000; email: [email protected]; website: easa.europa.eu. You may 
find the EASA material on the EASA website at ad.easa.europa.eu.
    (4) You may view this material at the FAA, Office of the 
Regional Counsel, Southwest Region, 10101 Hillwood Parkway, Room 6N-
321, Fort Worth, TX 76177. For information on the availability of 
this material at the FAA, call (817) 222-5110.
    (5) You may view this material at the National Archives and 
Records Administration (NARA). For information on the availability 
of this material at NARA, visit www.archives.gov/federal-register/cfr/ibr-locations or email [email protected].

    Issued on March 4, 2026.
Steven W. Thompson,
Acting Deputy Director, Compliance & Airworthiness Division, Aircraft 
Certification Service.
[FR Doc. 2026-04526 Filed 3-6-26; 8:45 am]
BILLING CODE 4910-13-P